Media supply receptacles, often paper trays, are included on most image forming/rendering apparatus, such as printers, scanners and photocopiers, for supplying printable media, commonly sheets of paper, to the image forming apparatus. Media adjustment guides, also called paper side guides, are included on many media supply receptacles for further accommodating nonstandard sized media, such as envelopes and postcards. Most media adjustment guides are designed to keep the stack of media in the media receptacle organized before it enters the image forming/rendering portions of the apparatus.
Adjustable, side by side poles or rods can be used as side guides for preventing dishevelment of a stack of documents in an automatic document feeding device for a machine for scanning and digitization of documents. These side guides control stack straightness, but generally do not assist in the control of skew, or rotation, of the documents.
In general, control of paper skew in printer paper trays is often accomplished with an elongated (relative to the length of the media) control edge, which is held in alignment with a document feeder. In order to accommodate a full range of media stack heights, the guides having these control edges must be relatively high. Unfortunately, tall fixed-height guides restrict operator access to shorter stacks of media, and complicate loading and adjustment of documents in the feeder.
Some automatic document feeding systems incorporate a moving platen input tray or input tray to elevate a stack of documents for feeding. In such systems attachment of document side guides in relation to the moving platen/stack support mechanism results in reduced precision in parallelism between the guides and the feeding mechanism due to tolerance build-up.
The present invention is a media receptacle for use with an automatic document feeding device in a machine for scanning and digitization of documents or the like. The receptacle comprises a horizontal base plate with adjustment guide members vertically mounted on it, and a movable, slotted input tray generally parallel to and above the base plate. The adjustment guide members include control rods which project through the control slots in the input tray. Guide caps on the upper ends of the guide members prevent the input tray from being easily removed, and guide the edges of the media. The control rods support the guide caps and allow elevation of the input tray, which is raised or lowered to accommodate varying numbers (capacity) of media sheets.
The present invention conveys three major benefits. First, the combination of control rods and guide caps receptacle adjustment guides of the present invention have optimized guide surfaces for a wide variety of document stack heights. Both document skew and dishevelment of the stack of documents are controlled. Secondly, the tops of the adjustment guides combination of control rods and guide caps do not project substantially above the paper stack, so the operator of the image forming apparatus has better visual and manual access to the document stack and the receptacle. This would not be the case in conventional one piece edge guides that are typically sized with a height slightly larger than the maximum intended media stack height. An example of this advantage is the case where an operator only needs to feed a small stack height say one to ten sheets of paper. In a conventionally configured edge guiding system, the edge guide would be sized at about five inches of height in order to allow for the feeding of a 1,000 sheet stack. In this instance, the operator would need to contend with an edge guide with approximately four or more inches of unnecessary height, thereby causing reduced visual and manual accessibility. In the present invention, the control rods and guide cap combination allows for the maximum capacity case, but will also allow the input tray to be raised to a level where only the edge guiding cap is exposed. This allows the operator to feed small and large stacks with optimized visual and manual accessibility. This increased accessibility translates to increased productivity and operator satisfaction. Thirdly, the media adjustment guides combination of control rods and edge guide caps of the present invention are adjustable for a wide variety of media widths.
The present invention includes media adjustment guides which combine the attributes of control rods for stack control and long guiding faces for skew control. The adjustment guide members of the present invention are shaped like pick-type combs. These guides improve operator access to the document stack by coordinating the height of the guides to the loading position of the movable platen input tray/stack support. The present invention also provides improved control of stacks of input documents during feeding. In addition, the adjustment guides are mounted directly to the frame of the image forming machine, and not to a movable input tray elevator platen. This reduces tolerance build-up and provides more consistent alignment of the adjustment guides to the feed mechanism.
The present invention provides an optimized paper guide approach with the benefit of an optimized height guide for any given stack. The media receptacle of the present invention largely prevents a media stack in the receptacle from becoming disheveled and prevents the sheets of media in the stack from becoming skewed. The present invention controls dishevelment and skew even in tall or very short media stacks. Also, the media receptacle of the present invention is adjustable for various media widths and lengths. Another advantage of the present invention is that it can be operated manually or automatically, as in the case of a photocopier or printer paper supply.